The motor-driven remote-control rearview mirrors of this type are used on many vehicles externally thereof. The details of such electric remote-control rearview mirror are disclosed in the U.S. Pat. No. 3,609,014. FIG. 1 is a sectional view of this type of power operated remote-control rearview mirror assembly. A backing plate 2 supporting a mirror 1 is mounted on a pivot 4 for horizontal and vertical angular movement therearound. The backing plate 2 is supported by means of the pivot 4 fixed to a mirror shell 3 and which is fitted in a spherical seat 4a provided on the opposite side of the backing plate 2 to that where the mirror is located. Further, two drive motors 11 for angular movement of the backing plate 2 are provided as fastened within the mirror shell 3, one for the horizontal angular movement of the mirror 1 and the other for the vertical angular movement. Each motor 11 is provided with a worm gear which is in mesh with a reduction gear 9. The reduction gear 9 has screwed through the center thereof a rod 8 which is directed perpendicular to the output shaft of the motor 11. That is, the reduction gear 9 has formed therein along the center axis a threaded hole and the rod has formed on the outer circumference thereof a thread corresponding to that of the hole. Thus, the rotational movement of the reduction gear 9 is converted to linear movement of the rod 8. The end of the rod is formed like a ball which is fitted in a spherial seat 6 provided on the backing plate 2. The ball portion 7 of the rod 8 and the spherical seat 6 form together a ball joint, and a hair pin-shaped spring 12 is provided as engaged in the recess formed in the ball portion 7 and pinching the ball portion 7, for thereby preventing the rod 8 from being rotated around the axis thereof.
The conventional remote-control mirror assemblies are build as having been explained in the above. However, the hair pin-shaped spring 12 provided pinching the ball portion 7 in the recess cannot provide complete prevention of the rod 8 from being rotated. Specifically, when the rod 8 is extended as shown in FIG. 1, the rod cannot be fully prevented from being rotated, and also the backing plate 2 cannot be stably supported, resulting in the oscillation of the mirror 1 during the running of the vehicle.
The present invention has the object to overcome the above-mentioned drawbacks of the prior-art motor-driven remote-control mirror assemblies, by providing a power operated remote-control mirror assembly of which the mirror can be positively angulated to an intended position and stably kept there without any vibration of the mirror surface even while the vehicle is running.